Blob Blame History Raw
From e28ef9414787f61029603500d746772c0ccd9635 Mon Sep 17 00:00:00 2001
From: "Mauro S. M. Rodrigues" <maurosr@linux.vnet.ibm.com>
Date: Thu, 23 May 2019 16:11:12 -0300
Subject: [PATCH 28/35] ixgbe: Check DDM existence in transceiver before access
Git-commit: 655c91414579d7bb115a4f7898ee726fc18e0984
Patch-mainline: v5.3-rc1
References: git-fixes

Some transceivers may comply with SFF-8472 but not implement the Digital
Diagnostic Monitoring (DDM) interface described in it. The existence of
such area is specified by bit 6 of byte 92, set to 1 if implemented.

Currently, due to not checking this bit ixgbe fails trying to read SFP
module's eeprom with the follow message:

ethtool -m enP51p1s0f0
Cannot get Module EEPROM data: Input/output error

Because it fails to read the additional 256 bytes in which it was assumed
to exist the DDM data.

This issue was noticed using a Mellanox Passive DAC PN 01FT738. The eeprom
data was confirmed by Mellanox as correct and present in other Passive
DACs in from other manufacturers.

Signed-off-by: "Mauro S. M. Rodrigues" <maurosr@linux.vnet.ibm.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
 drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c | 3 ++-
 drivers/net/ethernet/intel/ixgbe/ixgbe_phy.h     | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
index 0fe0ff00f2ce..0c753433595a 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
@@ -3252,7 +3252,8 @@ static int ixgbe_get_module_info(struct net_device *dev,
 		page_swap = true;
 	}
 
-	if (sff8472_rev == IXGBE_SFF_SFF_8472_UNSUP || page_swap) {
+	if (sff8472_rev == IXGBE_SFF_SFF_8472_UNSUP || page_swap ||
+	    !(addr_mode & IXGBE_SFF_DDM_IMPLEMENTED)) {
 		/* We have a SFP, but it does not support SFF-8472 */
 		modinfo->type = ETH_MODULE_SFF_8079;
 		modinfo->eeprom_len = ETH_MODULE_SFF_8079_LEN;
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_phy.h b/drivers/net/ethernet/intel/ixgbe/ixgbe_phy.h
index 00de4b6c4f89..fb73b812adfc 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_phy.h
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_phy.h
@@ -70,6 +70,7 @@
 #define IXGBE_SFF_SOFT_RS_SELECT_10G		0x8
 #define IXGBE_SFF_SOFT_RS_SELECT_1G		0x0
 #define IXGBE_SFF_ADDRESSING_MODE		0x4
+#define IXGBE_SFF_DDM_IMPLEMENTED		0x40
 #define IXGBE_SFF_QSFP_DA_ACTIVE_CABLE		0x1
 #define IXGBE_SFF_QSFP_DA_PASSIVE_CABLE		0x8
 #define IXGBE_SFF_QSFP_CONNECTOR_NOT_SEPARABLE	0x23
-- 
2.16.4